Honing machine



Feb. 21,1939. H. L.. .BLOOD I *HONING MACHTNE Filed sept. 23, 193e 5sheets-sheet 1 LJ/l, hmm- 1 what; a.; @l fw/ 5 s M f nl.: |\.r l |.n. I5 m. fi# :V z f... E; L. 1 f. fr Il`k 0 A d 8 7 8 7 4. 9 J 5% 6 6 n 5 Qm a a 7# w .2u 7 g2 9 3 w .0 2 Z 7 Feb. 21, v1939. H, 1 BLOOD 2,148,337

HONING MACHINE' Filed sept. 23, 193e 5 sheets-sheet- 2 Jaa .113 JIZ Feb.21, 1939, L L LOOD 2,148,337

HONING MACHINE Filed sept. 23, 193e A 'sheets-Sheet 3 Feb. 2l, 1939.l vH. L. BLOOD; l v L 2,148,337

HONING MACHINE Filed sept. 23, 193e 5 sheets-sheet 4 Feb. 21, .1939. IH, L. BLOOD 2,148,337

HONING MACHINE i Patented Feb. 2l, 1939 'UNITED STATES PATENT OFFICEHONING MACHINE Harold L. Blood, Worcester, Mass., assignor to The HealdMachine Company, Worcester, Mass., a

corporation of Massachusetts Application September 23, 1936, Serial No.102,147

14 Claims. (Cl. 51-9V5) The present invention relates to a honingmachine and particularly to a machine for the successive honing of aplurality of similar workpieces, all to the same predetermined finisheddimens on.

In prior devices of this character the honing operation has generallyremoved such a relatively small amount of material from the workpiecethat it has been considered unnecessary to control the finished size bya size-controlling device, especially when the workpiece has beenaccurately machined before honing. Where vthe dimension of the honedworkpieces must be accurately controlled, within close limits however,l5' a size-controlling device has b een found desirable and one of theprincipal objects of the present in.

vention is, accordingly, to provide a size-controlling mechanismv in a.honing machine so that the Y honing operation will be brought to a closewhen 2O the workpiece has been honed precisely to a predetermineddimension.

In applicants prior copending application.

Serial No. 100,911 led Sept. 15, 1936, is disclosed a hone structure inwhich the wear on the honing members is automatically compensated for bya mechanically actuated device which is entirely automatic and operatesindependently of the individual honing operations on successiveworkpieces so that compensation for wear on the honing members occursonly when necessary and independent of the number of workpieces honed.

This type of compensation, in general, is entirely satisfactory,although where a honing machine is controlled and actuated byfluidpressure actuated mechanisms it is desirable to provide a fluidpressure actuated mechanism for compensating for the wear on the hones.Thus, a further feature of the present invention is the provision of a`fluid pressure actuated mechanism by which to 40 procure a compensationfor wear on the individual piece before the hone is Withdrawn axiallyfromthe workpiece. This is true in the honing of either internal orexternal surfaces of workpieces and in the honing of cylindrical bor'esthe hone must be contracted to permit its entry within the unhoned borewithout damage to the honing members. A further feature of the presentinvention resides in the provision of a mechanism for automaticexpansion and contraction of the hone automatically in predeterminedrelation to the relative .axial movement of the hone and work- 5 piecewhich brings the workpiece into operative relation with the hone andwithdraws it therefrom.

Other and further objects and advantages of the invention willhereinafter more fully appear 10 from the following detailed descriptiontaken in connection with the accompanying drawings in which- Fig. 1 is aside elevation of a machine embodying the invention, with parts brokenaway to show 15 certain features.

Fig. 2 is a vertical sectional view through a part of the machine ofFig. 1, showing the hone in operative position.

Fig. 3 is a fragmentary vertical section showing 20 parts of the tablecontrolling and actuating mechanism therefor. i

Fig. 4 is a vertical sectional view corresponding to Fig. 2, but showingthe gage within the bore of the workpiece. 2 Fig. 5 is a side elevationof a detail with parte in section.

Fig. 6 is a horizontal sectional view along the line 6 6 of Fig. 2.

Fig. 'I is a horizontal sectional view substan- 30 tially along the line1-1 of Fig. 1.

Fig. 8 is a fragmentary vertical section alon the line 8--8 of Fig. 7.

Fig. 9 is a'iluid pressure diagram.

Fig. 10 is a vertical sectional view of va modified 35 form of thestructure which supports and controls the hone.

Fig. 11 is a fragmentary sectional view of a part of the mechanism ofFig. 10.

Fig. 12 is a horizontal sectional view along the 40 line |2-|2 of Fig.10.

Fig. 13 is a fragmentary fluid pressure diagram for the structure ofFigs. 10 to 12.

Like reference characters refer to like parts in the different figures.

With reference to Fig. 1, the machine, which discloses one embodiment ofthe invention, comprises a base I having a standard 2 and a horivzontalextension 3, in the upper end of which is journalled a spindle 4carrying ahon e 5. The 50 workpiece a is mounted in a suitable chuck 6of any desired character, and the chuck is carried by a bracket 'lforming part of a reciprocatory table 8. 'I'he latter is mounted forvertical reciprocation on guideways 9, Fig. 7, provided by the 55standard 2, and the workpiece is in axial alinement with the hone, thetable being moved up wardly to cause the hone to enter within the boreof the workpiece and procure a honing operation thereon.

'Ihe table is reciprocated preferably by uid under pressure and as shownin Fig. 2, the mechanism comprises a cylinder III secured within thestandard 2 and having a piston II, whose outwardly extending piston rodI2 is secured to a lug I3 on the table. Fluid under pressure isalternately directed to opposite ends of the cylinder for procuring thevertical reciprocatory movement of the table by means of a reversingvalveI I4, the position of which is controlled by a pilot valve I5, Fig.3, hereinafter more fully described.

vThe pilot valve is shifted for reversing the direcf tion of the tablemovement by means of a reversing lever I8, Fig. 3; in the form of a bellcrank lever. one end of which engages with the projecting end of thepilot valve. 'I'he opposite end of the bell crank lever extends intoalinement with reversing dogs I1 and I8 on the table which alternatelyengage and rock the reversing lever. When the hone is in operativeengagement with the workpiece the latter is vertically. reciprocatedover the hone with the reversing dogs determining the opposite ends ofthe reciprocatory movement.

When the honing operation is completed the reversing dog I8 is renderedinoperative and allows the table to have an extended downward movementinto the position of Fig. 1 for withdrawing the hone from the workpiecebore. With reference to Figs. 2 and 3, the reversing dog I8 is carriedon the end of a horizontally slidable rod I 9. which, when the honingoperation is completed, is moved to the left (from the position shown)under the influence of a gage hereinafter described, and this movementof the shaft VI9 procures turning movement of the dog I8 on itspivotpin-2Il as a result of engagement between a projecting arm 2| on saiddog and a pin 22 mounted in the table 8, so that the dog assumes theposition of Fig. 4 out of alinement with the reversing lever.

The gage 23 is in the form of a plug positioned in alinement with theworkpiece bore and adapted to enter the end thereof when the latter ishoned to the desired size. The gage is carried on the end of a rod 24vertically slidable in the bracket i 1 and said rod has a conical collar25 thereon for effecting movement of the rod I8. The left hand (Fig. 2)end of the rod I9 is enlarged and has a slot 26 through which the rod 24extends vand an adjustable screw 21 projecting into the slot is in aposition for engagement with the collar as the latter iscarried'upwardly by entry of the gage within the workpiece.

The gage is normally urged upwardly toward the workpiece by a coilspring 23 surrounding the rod and located between the collar 25 and aprojecting bearing 25 integral with the table. The rod 24 has at itslower end, an enlarged head 30 positioned within a'cup 3| secured to thebase I and vertically adjustable therein. The cup has a central opening32 for the rod 24. Invthe arrangement showh the base has a threaded bore33 for engagement with the threads 34 on the lowerv end of ythe cup 3|.The inwardly extending flange 35 at the opening 32 at the upper end ofthe cup engages with the head 30 to limit the upward movement of thegage as the workpiece moves upwardly into operative position.

When the workpiece isin operative position and is shifted verticallyupward, (causing a relative movement of the hone toward the lower end ofthe workpiece), the gage is drawn away from the workpiece to avoidengagement between the gage and the end of the hone. As the workpiecemoves downwardly in operative position, the gage is allowed to move intocontact with the end of the workpiece and when the workpiece is honed tothe desired size the gage enters therein. When this occurs, the partsassume the position of Fig. 4, with the collar 25 engaging with theadjustable screw 21 procuring the above mentioned movement of the shaftI9 to the left and rendering the reversing dog I8 inoperative, therebywithdrawing the workpiece from engagement with the hone.

After the finished workpiece has been removed from the machine and anunhonedworkpiecel placed in the workholder, the gage is unable to enterthe unhoned bore and is restored to the position of Fig. 1 relative tothe workpiece, thereby moving the collar 25 downwardly out of engagementwith the screw 21. The shaft I9 is then returned to the position ofFigs. 1 and 2 by means of a coil spring 3B surrounding the rod I9between a bracket 31 secured to the table, and adjustable nuts 38 onsaid shaft. The nuts 3B limit the movement of the rod I9 to the right byengagement with a portion of the table and thereby control thewperativeposition of the reversing dog. The dog is moved into the position ofFigs. 2 and 3 in readiness for the subsequent operation by a cam 39 onthe standard 2, which,

during the movement of the table upwardly .into operative position,engages vwith the arm 2I on said dog and procures turning movement ofsaid dog on its pivot pin 20.

With reference to Fig. 2, the hone 5 which is adapted for expansion andcontraction, is made up of a plurality of honing stones 40suitably'secured to carriers 4I located in radial slots 42 in a sleeve43 secured to the spindle 4. Flat springs 44 attached to the sleeve 43at opposite ends of each of the carriers 4I hold the latter within theslots and normally urge said holders inwardly against the conical end 45of a rod 4B axially slidable within the spindle 4 and sleeve 43, saidrod, by its axial movement procuring expansion or contraction of thehones.`

The spindle 4, which is journalled in the horizontal extension 3 of thestandard, has secured thereto, as by a key 41. a ring gear gear 48engageable with a pinion 49 on the end of a shaft 5I)4 journalled in theextension 3 and connected to a driving motor 5|, Fig. 1, which providesfor rotation of the hone, andA also for rotation of a fluid pressurepump 52 located between the motor and the pinion.

The rod 46 is axiallyslidable within the spindle yIl and has a key 53movable in a keyway 54 in the shaft to provide for axial movement ofsaid rod without turning movement relative to the spindle. The downwardmovement of the rod 45, which procures expansion of the hones, islimited by a nut 55 in threaded engagement with the rod and engagingwith the upper end of the sleeve or spindle 4. The upper end of the rod46 carries a piston 56 movable ina cylinder 51 in a housing 58 mountedon the extension 3 and coil springs 59 positioned between the upper sideof the piston and the end of the cylinder urge the rod 46 resilientlydownwardly for expanding the hone into engagement witlfthe workpiecebore. Fluid under pressure is admitted to\the underside of the piston 56through a suitable conduit 60, at

the end of the honing operation, to provide for contraction of the honeso that the latter will be withdrawn radially lfrom engagement with theTo compensate for wear on the honing ,stones the nut 55 is turnedslightly on the rod 46 when compensation is necessary so that during thesuccessive honing operation the hone carriers 4I will be moved aslightly greater distance outwardly byA 63 'on the upper end of the nut55. The collar 6I,

as best shown in Fig. 6, has a segmental recess 64 in which'is receivedthe end of a pin 65 projecting from the rod 46, so that the collar 6|may turn relative to the rod 46 through a small angle.

` The collar 6l is normally held in the position of the rod 46, duringFig. 6, relative to the rod .46 yby a coil spring 66 positioned withinthe recess.

When the hones are reduced in size by wear so that a compensation forwear is required; a fluid pressure actuated plunger 61, Fig. 2, slidablein a recess' in the housing 58, in which the cylinder 51 is located,engages with the collar 6| to hold the latter against turning movement.With the rod 46 4turning in the direction indicated by the arrow, Fig.6, and with the collar 6| held against turning movement, it will beapparent that the nut 55 will be turned on the rod 46 a predator- 'minedamount, controlled by the length ,of the segmental recess 64, Aand willaccordingly allow the subsequent honing operations, to move downwardly aslightly greater distance than before. After this compensation has takenpla-ce and the fluid pressure on the plunger 61 has been relieved, thecollar 6| is returned to the `position of Fig. 6 by means of the spring66, since the ratchet teeth are eective only in one direction.

The hones do not, in general, wear to such an amount that a compensationis necessary during each honing operation since only a small amount ofstock is removed from the workpiece. The

honing operation is preferablycompleted within -a predetermined numberof reciprocatory strokes of the workpiece relative to the hone. If thehoning operation takes more than this predetermined number of strokesthe honing stones are not eX- erting enough pressure against the workand a compensation for wear is necessary. If the compensation occursbefore necessary the proper surface nish is not obtained. In order thatthe compensation may take place only when necessary so that the honingoperation may be com- 'pleted within the predetermined number ofreciprocations, the compensatory mechanism has been arranged to functionindependently of the number of honing operations performed by themachine.

With reference to Figs. 1 and 5, the table 8 has a projecting dog 69,which, when the table is in operative position, engages with the end ofan arm 10, journalled on a stud 1i, to procure oscillation of thelatter. A pawl 12 is carried by the end of said arm and urged by aspring 13 into engagement with' a ratchet 14 journalled on the same stud 1| on the standard 2. A pin 15 in the standard 2 limits the downwardmovement of the arm 1I] which is urged resiliently downwardly by aspring 16 also mounted on the standard. I'he sition of Fig. 1. Y worn tosuch an extent that the honing operation in the standard 2 'fromposition the valve 9| is released and ratchet is normally urgedcounterclockwiseby a coil spring 11 surrounding the stud 1I and havingone end engaging with a pin 18 on the standard 2,.

and the other end engaging in an opening 19 in the ratchet. A secondpawl 80 journalledon a pin 8l on the standard 2 is held resiliently inengagement with the ratchet by aspring 82 to prevent counterclockwisemovement ofthe ratchet.

A lug 83 on the ratchet is in a position for engagement with aprojecting end of a valve 84 in a valve casing 85 secured to thestandard. When the valve is shifted by the lug 83 a compensation forwear of the honing stones takes place, since fluid under pressure isdirected to the recess 68 to shift the plunger 61, as will behereinafter described. The ratchet is normally in the position of Fig.1, with the lug a substantial distance from 84. For each reciprocationchet is advanced clockwise a 83 spa-ced angularly the end of the valveof the table the ratpredetermined number of teeth in response to theoscillation of the arm 16 by the dog 69 on the table.

Ifthe gage enters the bore of the workpiece be fore the valve 84 isshifted by the lug 83 no compensation for wear takes place, and when thetable reaches the inoperative or loading position of Fig. l, the ratchetis allowed to return to its original position in readiness for thesubsequent honing operation. To this end the table 8 has a projectingbar 86, Fig. 1, having `a shoulder 81 engageable with the pawl 80 torock the latter out of engagement with the ratchet. The dog 69 iswithdrawn from engagement with the arm 1D as the table moves downwardly,and the arm 16 also moves downwardly, bringing an extending arm 88 onthe pawl 12 into engagement with a cam 89 carried by the standard 2.This cam causes withdrawal of the pawl 12vout of engagement with theratchet so that the latter may be turned counterclockwise by the spring11 into the normal po- When the hones have become is not completedbefore the Valve 84 is shifted by the lug 83, a compensation for weartakes place. Thus the compensation for wear on `the stones takes placewhen necessary and independently of the number of honing operationsbetween successive compensations.

s above stated, the hones are expanded when the hone has entered theworkpiece and are contracted before the workpiece is fully withdrawnfrom engagement therewith. With reference to Figs. '7 and 8, a valvecasing 90 is mounted withand has a valve 91 slidable therein, Fig. 1.The. valve has a projecting end 92 in a-pcsition for engagement by a cam93 secured to the table. As the workpiece reaches operative position thevalve 9| is shifted by the cam 93 to allow fluid under pressure toexhaust from beneath the piston 56, thus allowing the hone to expandinto operative position, and as the moves downwardly to withdraw theworkpiece fluid pressure isagain directed to the underside of the piston56, thereby elevating the piston and contracting the hone. The cam 93 ispreferably located in a position to procure the expansion andcontraction of the hone while the workpiece is in operative honingposition.

With reference to Fig. 9, which shows the fluid pressure diagram indetail, the pump 52 draws fluid under pressure through a conduit thetank 85 which is positioned within the standtable ard. Fluid underpressure from the pump 52 is several valve mechanisms, the pressure inthis conduit 96 being controlled by a relief valve 91 in an exhaustconnection 98 from the pump to the tank.

For controlling the table movements the pilot valve I5, which is locatedin the valve casing 99, controls theposition of I4 by which site ends ofthe table cylinder I0, the reversing valve |4 being located in a casing|00 attached to the table cylinder I0.' The pressure conduit 96 isconnected by another conduit IOI to a port |02 in the pilot valve casing99, and iluid under pressure passes selectively from the port |02 -toeither of two spaced ports |03 or |04 in the casing 99, these portsbeing and |06 respectively, to opposite ends of the reversing valvecasing |00. The pilot valve has two tionbetween an outlet port in thecasing spaced reduced portions |01 and |08 and when uid under pressureis admitted to one of the ports |03 or |04 by one reduced portion,`theother of these ports is connected by the other reduced portion to one oftwo spaced exhaust ports |09 and I0 in the pilot valve casing. Theselatter ports are connected by conduits III and-I l2 to the exhaustconnection 98.

With the pilot valve in the position shown, which is the position of thevalve during upward movement oi the table, fluid under pressure passesthrough the conduit |06 and urges the main reversing valve I4 into the'position shown so that iiuid under pressure is directed to the lowerend of the table cylinder. As shown, a

conduit II3 provides a connection between the l conduit IOI and twospaced inlet ports |I4 and I I5 in the reversing valve casing I00. Achannel I I6 in the table cylinder provides a fluid connec- |00 and thelower end of the table cylinder and a channel I|8 provides a connectionbetween an outlet port I|9 in the casing |00 and the upper end of thetable cylinder.

to the conduit III exhaust connection 98.

two spaced reduced portions |22 and |23 which' provide iluidconnectionbetweenthe ports I I4 and I |9 or the ports ||5 and Il'l selectively,the opposite one of the ports`| I1 or |I9 being connected to the exhaustport |20. Shifting of the pilot valve I5 will shift the reversing .valveI4 and accordingly reverse the direction of movement of the table.

To prevent upward movement of the table beyond the normal operativeposition, the channel ||8 is spaced a short distance from the extremeend of the cylinder I0, and if the piston I| moves beyond the end ofthis channel the exhaust oi4 fluid through the reversing valve is cutoff. To permit downward movement of the table from a position where thepiston II covers the end of the channel I|8, a by-pass |24, having a'ball check valve |25 therein, provides a connection from the channelIIB to the extreme upper end of the table cylinder to allow the entranceof fluid under pressure to the end of said cylinder.

As above stated, the valve 9| controls the expansion and contraction ofthe hone. Referring again to Fig. 9, connected to a port |26 in thecasing 90 and the conduit 60, above referred to, is connected to a port|21 in the same casing. The valve 9| is normally held in the positionshown by a coil spring |26, so that iiuid under pressure is directedaround a reduced portion |29 of said valve .to the the main reversingvalve iiuid is directed alternately to oppov connected by conduits |05 lAn exhaust port |20 in the casing |00 is connected by a conduit I2Inected to the reversing lever procures movement of the pilot the fluidpressure conduit |0| is' underside of' the piston 56, urging the latterupwardly and thereby collapsing the hone. As the work reaches operativeposition the valve 9| is shifted to the right, as above stated, closingthe port |26 and providing fluid connection from the port |21 to a port|30 connected by a conduit |3I to the exhaust conduit I I, thus allowingfluid to exhaust from the cylinder 5l so that the piston can movedownwardly and procure expansion of the hone for the honing operation,the expansion being limited by engagement between the nut 55 and the endof the spindle 4.

The mechanism which provides for compensation for wear is actuated byiiuid under pressure, as above stated. Referring again to Fig. 9, theiiuid pressure conduit 96 is connected by a short circuit |32 to a port|33 in the casing 85. A port |34 in the same casing is connected by aconduit |35 to the recess 68. The valve 64 is normally in the positionshown in which the reduced portion |36 of the valve provides fluidconnection between the port |34 and an exhaust port |37 connected by aconduit i38 to the exhaust conduit When compensation for wear becomesnecessary the lug 83 procures movement of the valve 84 to the right,allowing uid under pressure to enter the recess 68, shifting the plunger6'! to the left to lock the collar 6I frictionally against turningmovement. When the collar is held against turning the relative turningmovement of the collar on the spindle (limited by the length of thesegmental recess) procures a corresponding turning movement of the nut55 on the rod 46 to allow the rod to.move slightly farther downwardlyduring subsequent honing operations.

In operation, the machine, when at rest, is in the position of Fig. 1,in which is shown an unhoned workpiece a, the internal diameter of whichis too small to allow the gage 23 to enter therein. The gage isaccordingly held in the position shown, with the collar 25 on the gagerod in such relation to the adjustable screw 21 that the rod I9 is inthe right hand position of this figure. To set the machine in operation,the operator turns the handle |39, Fig. 1, which is directly con- |6 andthereby valve I5 to the left into the position of Fig. 9 for upwardmovement of the table into operative position. As

the table moves upwardly into operative posir table reaches operativeposition with the hone located 'within the workpiece, the hone, whichhas been contracted, is caused to expand by the shifting movement of thevalve 9|.

The hone having entered the bore of the workpiece and been expanded, theworkpiece is reciprocated in operative position until, during a downwardmovement of the table, the gage 23 enters the workpiece bore, therebyprocuring movement of the rod I9 to the left to render the reversing dogI8 inoperative. The table then begins its downward movement intoinoperative position. As the table begins its downward movement intoinoperative position, and before the hone is entirely withdrawn from theworkpiece bore, the cam 93 releases the valve 9| so that the latterreturns to the position of Fig. 9 and .causes a contraction of the hone.

During the honing operation, while the table is reciprocated inoperative position, the reciprocations procure a step-by-step clockwiseadvance of the ratchet 14. It` the honing stones are not worn to such anextent as to require adjustment gf the hone, the honing operation willbe brought o an end by entry of the gage in the'workpiece bore beforethe lug 83 is brought into engagement with the valve 84 and nocompensation for wear takes place. As the table moves downwardly intoinoperative position at the end of each honing operation, the ratchet 14is released and returned by the spring to its original posi# tion ofFig. 1 in readiness for the subsequent honing operation.

If there is a necessity for compensating for f wear on the hone, thereciprocations of the table procure a clockwise rotation of the ratchet'I4 far enough to procure shifting movement of the v, valve 84 by thelug 83, thereby introducing fluid under pressure to the right hand endoi the plunger 61.' When this occurs, the collar 6I is frictionally heldagainst turning until the nut 55 has been backed away on the rod 46 farenough to allow the honing stones to move radially outward to compensatefor the amount they have been reduced in size. v When compensation forwear occurs, the honing operation proceeds as before, with the lug 83withdrawn from the valve 84 as the result of the downward movement ofthe table at the end of the honing operation, so that the plunger 61 isbacked away from the collar 6| until a further compensation for wearbecomes necessary. r

In the modification of Figs. 10 to 13 inclusive, the compensation forwear on the honing stones is provided in a somewhat different mannerthan that abovel described. With reference to these igures, the honespindle 4l has secured thereto a sleeve 43' within which the honeactuating rod 46 is slidable. The spindle 4' has secured thereto .thedriving gear 48 for rotation of the hone 5 on the' end of thel sleeve43. A nut 55 is `in threaded engagement with the rod 46 and engages theend of the spindle 4 tolimit the downward movement of the rod 46 andthereby control the expanded position of the honing stones. Tothe upperend of the rod 46 is secured a piston 56 vertically slidable in acylinder v51. Coil springs 59' engage with the upper side of the piston55', normally urging the piston downwardly for expanding the hones; Thusfar the structure is the same as that of the original embodi- 4 ment` ofthe machine above described.

`To provide for the compensation for wear in this modification, thehousing 58 has positioned above the cylinder l a slightly largercylinder |40 in which is positioneda piston |4| directly above thepiston 56'; Fluid under pressure is normally directed to the upper sideof the piston |4| through a conduit |42, thereby holding the piston |4|in its lower position of Fig. 10 to limit `the upward movement of therod 46. The spindle 4 has an integral sleeve |43 surrounding andextending above the nut 55', and within the sleeve is positioned acollar |44 having ratchetl teeth |45 cooperating with correspondingratchet teeth |46 on the nut 55'. A shoulder |41 on th'e collar engagesthe end of `thesleeve |43 and normally holds the cooperating ratchetteeth out of engagement.

' When a compensation `for wear becomes necessary, the fluid underpressure above the piston `HH is allowed to exhaust, thereby allowingthe-piston 56 to move upwardly far enough for the cooperating ratchet teethto engage with each other. A continued upward movement of the rod 46"after the teeth are in engagement procures a rotation of the collar |44relative to the rod 46', since this collar has a. slot |48, Fig. 12,engageable with a pin |49 projecting from the rod 46'. The slot |48,however, extends at an angle to the center line of the rod 48 to producea slight turning movement of the collar |44 which results in acorresponding movement of the nut 55 on the rod 46. The backing ofl orturning of the nut 55 allows the rod to move downwardly a slightlygreater distance than before, to procure an increased expansion of thehone which compensates for wear on the honing stones.

With reference to Fig, 13, the valve casing 85' corresponds to thecasing 85, above described, with the exception that the port |33 isconnected to the exhaust conduit |38 instead of the uid pressure supply,and the port-|3'| is connected to the pressure supply conduit |32 ratherthan to exhaust. Thus, with the Valve 84 ln its normal position, fluidunder pressure is directed at all times through the conduit |42 to theupper side of the piston 4|. When compensation for wear on the stonesbecomes necessary, the valve 84 -is shifted to the right, as abovedescribed in constructure by which to compensate for the wearv on thesestones, independently of the individual honing operations. The machinealso provides a hydraulically actuated mechanism by which to collapsethe hone be'fore its withdrawal from the bore of the workpiece and toprovide for expansion of the hone when the latter is in a position forhoning. l

I claim,

l. In a honing machine, a hone comprising a. plurality of angularlyspaced honing members movable relative to each other and simultaneouslyengageable with a single surface of a workpiece, a work-support having aworkpiece positioned therein for engagement by the hone, a gage forterminating the honing operation when the workpiece reaches apredetermined size, and means for compensating fonwear on the hone.

2. In a honing machine, a hone comprising `a plurality of angularlyspaced honing members movable relative to each other and simultaneouslyengageable with a single surface of a workpiece, a work-support having aworkpiece posi` v:sis

tioned therein for engagement by the hone, a

gage for terminating the honing operation when the workpiece reaches apredetermined size, and means for compensating for wear on the hone,said last means being operative if the gage does not become operativeafter a predetermined period of honing.

3. In a honing machine, a hone comprising a plurality of angularlyspaced honing members movable relative to each other and simultaneouslyengageable with a single surface of a Workpiece, a work-support tionedtherein for engagement by the hone, a gage for terminating the honingoperation when the workpiece reaches a predetermined size, and meansfcrpprocuring a compensation for wear on the hone a predetermined timeafter the beginning of the honing operation.

having a workpiece posi` 4. In a honing machine, a. hone comprising aplurality of angularly spaced honing members movable relative to eachother and simultaneously engageable with a single surface of aworkpiece, a work-support having a workpiece posi-r tioned therein forengagement by the hone, a

gage for terminating the honing operation when the workpiece reaches apredetermined size, and uid pressure actuated means for procuringcompensation for wear on the hone a predetermined time alter thebeginning' of the honing operation.

5. In a honing machine, a hone comprising a plurality of angularlyspaced honing members movable relative to each other and simultaneouslyengageable with a single surface of a workpiece, a work-support having aworkpiece positioned therein, means for procuring a relativereciprocatlon between the hone and work-support when the latter is inoperative position, a gage for terminating the honing operation when theworkpiece reaches a predetermined size, and uid pressure actuated meansfor procuring a compensation for wear on the honing member after apredetermined number oi' reciprocations of the work-support relative tothe hone.

6. In a honing machine, a hone having at least one honing member movablerelative to the hone for expansion and contraction thereof, aworksupport having a workpiece positioned therein, a

gage adapted to enter the -bore of `the workpiece when the latterreaches a predetermined size for terminating the honing operation, anduid pressure actuated means responsive to the entry of said gage forcontracting the hone.

'7. In a honing machine, a hone having at least one honing membermovable relative thereto into and out of operative position, awork-support having a workpiece positioned therein, fluid pressureactuated means for shifting said honing member, means for limiting themovement of the member into operative position, and means for procuringa compensation for wear on the mem- `ber by automatic adjustment of thelimiting means.

8. In a honing machine, a hone having a plu-` rality of honing membersmovable relative thereto, fluid pressure actuated means for moving saidmembers for expanding and contracting the hone, a work-support having aworkpiece therein,

means for procuring a relative movementk between operation, and meansfor contracting the hone prior to said separation.

9. In a honing machine, a rotatable hone hav; ing a plurality of honingmembers movable relative thereto for expansion and contraction of thehone,I means for limiting the expansion of said hone, and fluid pressureactuated means for compensating for wear on the honing members byadjustment of said limiting means.

10. In a honing machine, the combination with a collapsible hone, of asize controlling mechanism having a feeler engageable with lthe surfaceof the workpiece being honed, and means under the control of the sizecontrolling mechanism for procuring collapse of the hone.

11. In a honing machine, the combination with a collapsible hone, of asize controlling mechanism having a feeler engageable with the surfaceof the workpiece being honed, uid pressure actuated means for collapsingthe hone, and means under the control'of the size controlling mechanismfor actuating said fluid pressure means.

12. In a honing machine, a hone comprising an arbor and a plurality ofangularly spaced honing members carried by said arbor and movablerelative thereto into and out of operative position, a

work-support, size determining means, and means under the control ofsaid size determining means for procuring a movement of the honingmembers relative to the arbor into inoperative position.

13. In a honing machine, a hone comprising an arbor and a plurality ofangularly spaced honing members carried by said arbor and movablerelative thereto into and out of operative position, a work-support,means for procuring a honing operation in a workpiece in said support,said honing operation including an axial reciprocation between said honeand workpiece, size determining means, and means responsive to said sizedetermining means for procuring movement of the honing members relativeto the arbor into inoperative position.

14. In a honing machine, a hone comprising an arbor and a plurality ofangularly spaced honing members carried by said arbor and movablerelative thereto into and out of'operative position, a work-support,means for procuring a honing operation in a workpiece in said support,said honing operation including an axial reciprocation between said honeand workpiece, size determining means and meansresponsive to said sizedetermining means for procuring movement of the honing members relativeto the arbor into inoperative position and withdrawal of the hone fromthe workpiece.

HAROLD L. BLOOD.

